Black carbon (BC) in urban and surrounding rural soils of Beijing, China: spatial distribution and relationship with polycyclic aromatic hydrocarbons (PAHs)

The concentrations of black carbon (BC), total organic carbon (TOC) and polycyclic aromatic hydrocarbons (PAHs) have been determined in soils from urban and rural areas of Beijing. The rural area can be divided into plain and mountainous areas which are close to and relatively far from the urban area, respectively. Concentration of BC (5.83 ± 3.05 mg g⁻¹) and BC/TOC concentration ratio (0.37 ± 0.15) in Beijing’s urban soil are high compared with that in world background soils and rural soils of Beijing, suggesting the urban environment to be an essential source and sink of BC. Concentration of BC in the urban area decreases from the inner city to exterior areas, which correlates with the urbanization history of Beijing and infers accumulation of BC in old urban soils. Black carbon in Beijing soils mainly comes from fossil fuel combustion, especially traffic emission. Median PAH concentration in the urban area (502 ng g⁻¹) is one order of magnitude higher than that in the rural plain (148 ng g⁻¹) and mountainous area (146 ng g⁻¹) where PAHs are supposed to mainly come from atmospheric deposition from the urban area. Concentrations of BC correlate significantly with those of PAHs (p < 0.01, except naphthalene) in the urban area and with those of heavier 4-, 5- and 6- ring PAHs (p < 0.01) in the adjacent rural plain area, while there is no significant correlation with any PAH in the farther rural mountainous area.     

重视“两票三制” 打造安全的电力企业

介绍了电力企业“两票三制”的管理制度,提出了加强“两票三制”管理措施。     

Do exurban communities want more development?

Most land-use surveys of exurban residents focus on eliciting preferences for residential development and open space conservation. This article, in contrast, reports on a stated preference study of exurban residents that assesses the relative attractiveness of a variety of commercial and recreational land uses. Focus group participants and town planners proclaimed a demand for certain commercial services such as modern grocery stores and fine-dining restaurants, but survey respondents generally exhibit a strong preference for no additional development beyond the current rate of development. Results show that if additional development is to occur, then recreational services are generally preferred over more traditional commercial development. Combining two commercial services in a single development project are strongly preferred to stand-alone developments. Our approach illustrates how planners may uncover misconceptions about and priorities for land conversion through examining residents’ preferences.     

农村环境保护的“四位一体”管理模式

农村环境保护是建设社会主义新农村的重要组成部分,加强农村环境管理是做好农村环境保护的关键。针对我国农村环境问题日趋严峻的状况,本文采用文献资料对比分析以及管理学等方法,论述了农村环境的现状,分析了农村环境问题产生的4个主要原因,提出了加强农村环境保护的政府、企业、社会、农村"四位一体"的管理模式,阐明了"四位一体"管理模式的主要内容,阐述了"四位一体"管理模式对于加强农村环境管理、解决农村环境问题、保护农村环境的重要作用。     

农村生活污水治理可行模式探讨

目前我国城市点源污染已经得到初步控制,为解决农村地区流域污染,改善农村人口饮用水条件、建设农村污水处理系统已刻不容缓。本文从污水收集、处理和污泥处置3个方面出发,阐述了农村地区不同污水收集模式、常见的污水处理技术和污泥处置方法的优缺点,提出可行的生态友好的农村污水处理模式,为农村污水处理系统的规划建设提供参考。     

川化股份有限公司循环经济竞争力评估研究

循环经济建设是从根本上缓解资源环境短缺与经济快速发展之间的尖锐矛盾的有效模式。本文对四川省发展循环经济建设成效较显著的试点企业——川化股份有限公司进行基于循环经济的企业竞争力评估。通过建立企业循环经济竞争力评估指标体系,采用数学模糊评估模型,系统分析了企业的基于循环经济的竞争力水平。报告的评估成果显示,经5年的企业循环经济建设,截止2009年,川化股份有限公司基于循环经济的企业竞争力总体处于“强”的水平。     

炼化企业污水处理场恶臭气体治理技术探讨

文章通过对几种恶臭气体处理工艺的对比分析,提出炼化企业污水处理场物化单元采用活性碳吸附-催化氧化处理工艺,生化单元采用生物滤塔处理工艺,并对两种工艺进行了介绍,指出该工艺具有一定针对性,能够达到较好的处理效果。     

Community-Based Technology Transfer in Rural Aquaculture: The Case of Mudcrab Scylla serrata Nursery in Ponds in Northern Samar,Central Philippines

Finding aquaculture development approaches to open up livelihood opportunities for the rural poor and in mainstreaming smallholder fish farmers to reduce poverty remain a challenge. This paper examines the community-based technology transfer mechanism of mudcrab nursery in ponds and its socioeconomic impacts on smallholder mudcrab growers in Northern Samar, Philippines. Results indicated that the technology is a viable enterprise done by a straight culture system method, which is the rearing of crablets from <1.0 to 4.0 cm for 42 days, or by-phases. However, technology adoption hinges on many factors like area ownership, farm distance from household, and market including the type of strategy needed to enhance technology uptake. Collaboration among research and development institutions and local partners is critical in training and empowering rural communities to adopt aquaculture technologies.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0528-5) contains supplementary material, which is available to authorized users.     

突破与引领 开启废钢铁产业发展新征程

2011年两家以废钢加工配送为主业的专业化金属再生资源公司双双跻身于中国企业500强,显现了我国废钢铁产业的成就和希望。指出创造一个具有中国特色的现代化废钢铁产业体系需要大企业骨干群体的创新和引领,打造大企业的着力点在于扩大规模、系统管理及承担社会责任,其动力核心在于突破和创新。     

我国农村环境的主要问题及其对策建议

农村环境是国家整体环境的重要组成部分,目前农村环境存在三大主要问题:生态破坏,乡镇工业污染和农业污染。作者认为在重点抓好城市环境保护的同时,不可忽视农村的环境保护工作,作者建议应从环境建没和环境监督管理两个方面采取若干措施以控制农村环境的进一步恶化。